label/flet: bug: empty case wallops symbol macros.

* eval.c (make_var_shadowing_env): We cannot return the
original env in the empty variable case, but earnestly
make a new one. This function is used by the expander when
walking the lbind/fbind special from emitted by labels/flet.
That form clobbers the environment via make_fun_shadowing_env,
which calls make_var_shadowing_env and then destructively
moves the variable bindings to the function binding slot of
the environment. The manifestation is that when we have
(symacrolet ((x 1)) (labels () x)), the x fails to expand; it
has been wrongly moved to the function bindings area of the
macro environment.

0 files changed, 0 insertions, 0 deletions